Construction plan for hydrogen production converter in refinery project

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1.1 Project Overview: Introduction to the Heating Furnace for the Oil Hydrogenation and Related Hydrogen Production Project at Shouguang Union Petrochemical Co., Ltd.
Shandong Union Chemical Group Co., Ltd. was established in 1970; it is a large-scale comprehensive chemical enterprise that ranks among the top 500 chemical companies in China and possesses the right to engage in import and export activities on its own. The group includes seven subsidiaries, such as Shandong Union Chemical Co., Ltd., Shouguang Union Petrochemical Co., Ltd., Shouguang Union Phosphorus Fertilizer Co., Ltd., Shandong Tianli Pharmaceutical Co., Ltd., Shouguang Xinfeng Starch Co., Ltd., Shouguang Union Chemical Machinery Co., Ltd., and a logistics company. The group employs over 5,000 people, covers an area of more than 1 million square meters, and has total assets of 3.3 billion yuan. Its main production capacities include 750,000 tons of synthetic ammonia, 1.2 million tons of urea, 500,000 tons of compound (mixed) fertilizers, 1 million tons of crude oil processing capacity, 500,000 tons of methanol, and 250,000 tons of sorbitol. In addition, it produces glucose, sulfuric acid, hydrochloric acid, 2-acrylamido-2-methylpropanesulfonic acid, as well as various types of pressure vessels; in total, there are more than 20 different types of products manufactured by this company. Over the years, the company’s key economic and technical indicators have remained at the leading level among similar enterprises across the country. In 2007, it achieved sales revenue of 4.04 billion yuan, taxes and profits of 570 million yuan, and a profit of 460 million yuan. The flagship product, \"Lianmeng\" urea, has passed the ISO9002 quality management system certification as well as the certification specific to urea products, and has been awarded the honor of being one of the first batch of products exempt from inspection by the **Quality and Technical Supervision Bureau**. 1.2 Business Terms 1.2.1 Subject matter: One set of heating furnaces for a 400,000 tons/year diesel and gasoline hybrid hydrogenation unit (this set consists of 1 reaction feed heating furnace and 1 bottom reboiler for the distillation tower, forming a combined heating system); one set each for the conversion furnace and the raw material preheating furnace in a 8,000 Nm3/h hydrogen production unit. All three sets of heating furnaces are manufactured through factory-based integral prefabrication and assembled on-site. 1.2.2 Method of contract award: ① Based on the provided design data, specifications, and equipment diagrams, the construction drawings shall be completed; after being reviewed by the engineering design unit and the client, the materials shall be procured for production and installation. ②Turnkey supply (including furnace tubes and lining), covering material preparation, manufacturing, inspection, transportation, installation, commissioning, acceptance, and related technical services ； Basic delivery. ③For all stages such as tendering/inquiry for the heating furnace tubes, contract signing, delivery, and acceptance, Party B must be under the supervision of Party A ； Before carrying out any of the tasks, Party B shall provide Party A with written notice in advance, so that Party A can send personnel to attend promptly ； If the aforementioned tasks are carried out without notifying Party A, the furnace tube will be deemed unqualified. ④The scope of the contract does not include the external anti-corrosion treatment of the equipment; the contractor for this task will be determined separately by the tendering party. ⑤Party B shall promptly report and resolve any issues that arise during the preparation and manufacturing of the heating furnace, so that Party A’s heating furnace can be delivered on time or even ahead of schedule, with guaranteed quality. All activities in which Party A participates do not exclude or reduce Party B’s responsibilities. 1.2.3 Delivery period: The construction drawings shall be completed and submitted within 30 days from the date the contract comes into effect; the preparation of materials for the heating furnace (excluding furnace tubes) shall be completed within 60 days; prefabrication at the factory and delivery to the client’s site shall be completed within 120 days; on-site assembly and lining work shall be completed within 150 days; and acceptance shall be completed along with the obtaining of quality certification and other necessary documents for commencement of work within 165 days. (Imported furnace tubes arrive within 120 days, while domestic furnace tubes arrive within 90 days.) Delivery date: Tentatively scheduled for July 15, 2009. Bidders may also propose their own delivery timeline ； The length of the supply period serves as an important criterion for bid evaluation. 1.2.4, Acceptance: The equipment shall be manufactured, installed, and accepted in accordance with **standards. 1.2.5 Delivery: Delivery location: the Party A’s construction site (Houzhen Industrial Park, Shouguang City). Measurement method: Upon the arrival of the equipment at the site, the weight will be determined based on the construction drawings and measured using the scale provided by Party A. If the negative deviation exceeds 5%, a deduction will be made from the total cost in proportion to the tonnage (the furnace tubes are measured separately; if their negative deviation exceeds 5%, a deduction will be made in proportion to the price of those tubes). If the negative deviation in the total weight (or the weight of the furnace tubes) exceeds 10%, the equipment will be considered unacceptable, and Party B shall bear all resulting losses. No additional cost will be incurred if there is a positive deviation in the weight. 1.2.6 Supervision of production and services: Party A has the right to send personnel at any time to supervise the process of material preparation and production by Party B. Party B must cooperate and provide necessary assistance, as well as offering free accommodation and meals for Party A’s supervision staff. The Party A’s supervision personnel represent Party A on a full authority basis; Party B should take seriously the reasonable suggestions and requests put forward by these supervision personnel and take appropriate actions in a timely manner ； If Party B refuses the suggestions and requests of Party A’s supervision personnel, it must provide reasonable and sufficient justification; otherwise, Party B shall bear responsibility for any delays in equipment delivery, quality defects, and other related losses that result therefrom, and shall be liable for compensation. 1.2.7 Quality assurance and other liability for breach of contract: (1) Party B shall prepare the materials, manufacture the equipment, and supply it in accordance with the drawings, technical requirements, and relevant standards and specifications provided by Party A; in the event of any conflict between the technical requirements and the relevant standards and specifications, the latter shall prevail. Pipes are selected from the large outer diameter series, while flanges use the HG20615～20635 standards, which are part of the American series. (2) Upon completion of supply, Party B shall provide the operating procedures for the heating furnace (along with an electronic version). (3) Party B shall assign professional technical personnel to supervise the installation, testing, and commissioning of the equipment ； If Party A requires it, Party B shall send personnel to provide on-site training to Party A’s operators. (4) In the event that resupply is required due to substandard supply quality (including damage and loss during transportation), it shall be treated as a delay in delivery. (5) Party B shall provide assemblage drawings, certificates of conformity, and relevant technical documents upon the delivery of the equipment. (6) After the device components arrive at Party A’s site, if any of the following conditions is detected during the initial inspection, Party B shall be responsible for returning or replacing them; if this affects the overall schedule of the project, it will be treated as a delay in delivery: ① The supplied components and materials do not meet the specifications, types, or manufacturer (brand) specified in the contract ； ②Damage to the surface or interior occurred during transportation ； ③Components, valves, instruments, etc., without factory documentation, CMC markings, or nameplates ； ④Upon preliminary inspection, the equipment, components, or materials fail to meet the design specifications ； ⑤Other quality issues that affect usability. 1.2.8 The quality warranty period for the entire set of equipment is 1 year. During this period, if any quality issues arise or the equipment fails to meet the design specifications after it is put into operation, Party B shall, within a period agreed upon by both parties, carry out repairs on the equipment or replace the relevant components or materials, bearing all associated costs. If the equipment still fails to meet the design specifications, one of the following solutions shall be adopted: ① Accept the equipment with concessions, deducting part of the remaining payment until it is fully covered ； ②Terminate the contract and compensate Party A for the losses incurred as a result. 1.2.9 In the event of problems arising from quality issues, upon receiving notification from Party A, Party B must send personnel to the site of Party A within 24 hours (within the province) or 48 hours (outside the province) to handle the situation. 1. Upon the expiration of the three-year warranty period, Party B will provide lifetime service, charging only the cost of the repair materials used, with no additional fees. 1.2.10 Acceptance, rejection, or modification of other provisions. Suggestions or targets for adjustments can be put forward regarding the delivery period and payment terms, but this will affect the chances of winning the bid at the same price. 1.2..11 During the process of equipment lifting, alignment, welding, etc. at Party A’s construction site, Party B must comply with the scheduling and instructions provided by Party A on site. In case of violations of Party A’s rules and regulations or failure to follow such instructions, a fine of 500 yuan will be imposed each time, and this amount will be deducted directly from Party B’s payment for the work done. 1.2.12 The Party B project manager is the primary person responsible for ensuring safe construction at the Party A’s construction site, and bears direct leadership responsibility for the safe execution of the projects assigned to them ； During the construction of the heating furnace, it is necessary to strictly implement the relevant guidelines, policies, laws, regulations, and rules regarding safe production, as well as to strengthen safety and civilization education for the construction workers. Party B shall be responsible for any construction safety accidents that occur during the installation of the heating furnace. 1.3 Construction Plan: The plan includes the construction plan for the main structure installation, as well as the construction plans for the furnace tubes and furnace lining. Four heating furnaces are located in the hydrogen production unit area. To reduce costs, the reactor feed heating furnace is a pure radiation heating furnace; expensive finned tubes are omitted. It shares a convective chamber with the reboiler at the bottom of the distillation tower, while the radiation chambers are arranged separately. One hydrogen production raw material preheater and one converter. 1.3.1 Project Characteristics (1) To ensure project quality and maximize prefabrication in the factory, it is necessary to carry out as much of the prefabrication work as possible at our company’s container manufacturing plant. (2) Numerous concurrent tasks lead to prominent safety issues. The construction process of heating furnaces is complex, involving many concurrent tasks – both between different stages of the work and among various types of workers. Therefore, strict organization and scientific planning are necessary to ensure safe construction. (3) The furnace wall panels have a large area and are thin, making them prone to deformation during welding; the quality of these wall panels directly affects the quality of the furnace construction. 1.3.2 The standards used for formulation include SH3065-1994, Technical Standards for Emergency Bend Pipe Fabrication in Petrochemical Tubular Furnaces; SH3085-1997, Welding Technical Requirements for Carbon Steel and Chrome-Molybdenum Steel Tubes in Petrochemical Tubular Furnaces; SH3086-1998, Technical Requirements for the Construction of Steel Structure Projects and Component Installation in Refinery Tubular Furnaces; SH3087-1997, Technical Standards for Heat-Resistant Steel Castings in Petrochemical Tubular Furnaces; SH/T3113-2000, Technical Standards for Burner Engineering in Petrochemical Tubular Furnaces; SH/T3115-2000, Technical Requirements for Lightweight Cast Lining Engineering in Petrochemical Tubular Furnaces; SH/T3523-1999, Welding Procedures for Chromium-Nickel Austenitic Steel, Iron-Nickel Alloys, and Nickel Alloys in Petrochemical Applications; HG/T2061-2000, Centrifugally Cast Alloy Tubes for High-Temperature Pressure Applications; GB150-1998, Steel Pressure Vessels; GBJ211-87, Construction and Acceptance Specifications for Industrial Furnace Masonry Works; GB13296-91, Stainless Steel Seamless Tubes for Boilers and Heat Exchangers; GB3087-82, Seamless Tubes for Low- and Medium-Pressure Boilers; GB5310-85, Seamless Tubes for High-Pressure Boilers; GB13296-91, Stainless Steel Seamless Tubes for Boilers and Heat Exchangers; GB9948-88, Seamless Tubes for Petroleum Cracking Applications; JB/T1610-93, Technical Requirements for Boiler Containers; JB4780-2000, Welding Procedure Qualification for Steel Pressure Vessels; JB/T6046-92, Post-Weld Heat Treatment Methods for Welded Components Made of Carbon Steel and Low-Alloy Steel; ASTM A213, Technical Requirements for Seamless Ferritic and Austenitic Alloy Steel Tubes for Boilers, Superheaters, and Heat Exchangers; ASTM A312, Seamless Welded Austenitic Stainless Steel Tubes; ASTM A335, Seamless Ferritic Alloy Tubes for High-Temperature Applications; ASTM SB564, Nickel Alloy Forgings; ASTM A608, Technical Requirements for Centrifugally Cast Nickel-Iron-Chromium High-Alloy Tubes for High-Temperature Pressure Applications; ASTM B407, Seamless Nickel-Iron-Chromium Alloy Tubes and Pipes. 1.3.3 The steel structure columns and beams of the furnace are prefabricated in depth at our company’s container manufacturing plant, including assembly and other processing steps. 1.3.4 Construction plan for the cylindrical furnace: On-site assembly of the furnace bottom plate and ring beams, as well as individual installation of the small columns at the furnace bottom and the furnace bottom ring beams. The convection chamber is prefabricated, the tube sheet is framed, the entire structure is lifted into place, and lining is applied at height. After the single-column installation and alignment are completed, first install the reinforcing angle steel framework in the reserved space, and then install the furnace wall panels. 1.3.5 Construction plan for the box furnace: For the radiation chamber of the box furnace, prefabrication is carried out in two sections along with one frame, in order to reduce the amount of work required during on-site installation. The furnace wall panels, columns, and reinforcement beams on both sides of the radiation chamber are prefabricated as two separate pieces each, while the two middle furnace wall sections are prefabricated as a single unit. Once these pieces along with the frame have been prefabricated, they are transported to the site for installation. After alignment is completed, the side walls as well as the furnace bottom and top are installed; the side walls are installed after the furnace tubes have been installed. The convection section is prefabricated as a whole, and can be installed once the radiation section has been installed. 1.3.4 Installation of the waste heat recovery system (1) Overview: This plan provides only a general description of the common aspects related to the waste heat recovery system. A waste heat recovery system mainly includes flues, air ducts, air preheaters, blowers, exhaust fans, butterfly valves, etc. (2) Construction of smoke and air ducts: 1) For pipes and equipment, ensure that their dimensions are correct; based on the actual conditions on site, try to increase the prefabrication depth as much as possible. 2) The flue ducts shall be hoisted in sections, and the welds made on-site shall undergo a kerosene leakage test. 3) Since there are few opportunities to disassemble the air ducts and it is difficult to do so, when using flange connections, the gaskets must be installed correctly from the start, and the bolt specifications must meet the requirements specified in the drawings. (3) Installation of the butterfly valve: The butterfly valve is supplied by Party A. Upon arrival, it must be carefully inspected. Under the supervision of relevant departments, checks should be carried out on the geometric dimensions of the valve as well as tests of its rotational performance. The geometric dimensions of the valve must meet the specified requirements; the shaft must rotate smoothly, the opening degree must conform to the design specifications, the indicator must show accurate readings, and the allowable air leakage rate after the valve is closed must meet the required standards. When installing butterfly valves, attention should be paid to the installation direction; the connection with the flue should be smooth, and after installation and welding, inspections and tests should be carried out in accordance with the design requirements. (4) Installation of air preheater 1) Overview The structure of the air preheater consists of three parts: the preheater body, the ash bed, and the support steel frame. The body is the core of the air preheater; this part consists of a tube box, a support frame, a connecting box, seals, and connectors. The tube box is the core of the air preheater’s body, and therefore the installation of the air preheater focuses mainly on the installation of its tube box. The ash hopper of the air preheater is mainly made of sheet metal and shaped steel, with a roughly square-cone shape, and is installed at the lower end of the main body. The support frame is a square frame. 2) Prefabricated installation of the support framework: The prefabrication of the support steel frame should meet the requirements of general steel structures. The support steel frame is prefabricated and lifted as a whole, with the overall verticality deviation after installation not exceeding 5 mm. 3) Air preheater installation: After the air preheater as a whole has passed the inspection upon arrival, it is lifted into place in its entirety. Pre-installation checks: Before installation, the external dimensions of the tube box should be checked, and dust, rust, and other debris inside and outside the tubes must be removed. The quality of the welding between the tubes and the tube sheet should also be inspected; if necessary, a kerosene leak test should be conducted. 4) Overall testing and inspection of the air preheater: After the installation of the tubular air preheater is completed, a pressure test is carried out simultaneously with the flue and air ducts, and there should be no leaks. (5) Fan installation 1) Construction preparation and unpacking inspection: Before starting work, a comprehensive technical briefing should be provided to the construction team; the workers must thoroughly familiarize themselves with the design drawings, accompanying technical documents, as well as the installation requirements, technical specifications, installation methods, and quality inspection standards. During unpacking and inspection, the quantity and serial numbers of the packaging boxes as well as their quality should be checked. After unpacking, the visual quality of the equipment and its various components should be inspected, to ensure that all accompanying technical documents are present. The components should then be counted in accordance with the packing list included with the shipment. 2) Disassembly inspection: Before the fan is installed in place, it can be decided whether to conduct a disassembly inspection based on the manufacturer’s technical requirements. Dismantling is carried out as follows: clean the components, check that the clearances between various parts of the bearing meet the requirements specified in the drawings and standards, and apply new lubricant in the grade and quantity specified in the accompanying technical documents. Check the ellipticity and deflection of the shaft, as well as the clearance of the impeller’s mouth ring; all these should meet the requirements specified in the accompanying technical documents and standards. Check that the air intake control flap of the fan rotates smoothly. 3) Before installing the a equipment in place, first check the installation quality of the exhaust fan support beam; its deviation should meet the following requirements. Using the center of the furnace body as a reference, determine the installation centerline of the exhaust fan on the support beam. Allowable installation tolerances for the induced draft fan support beams: Sequence Number, Item, Allowable Tolerance. 1. Levelness: L/1000 mm; 2. Elevation: ±3 mm; 3. Beam spacing: ±5 mm. Appropriate lifting tools and materials that have passed quality inspection should be selected based on the weight and dimensions of the equipment. b The fan installation must meet the following requirements: the deviation of the fan’s installation center position must be less than 5 mm. The levelness of the fan should be measured at the rotor shaft diameter; the deviation in axial levelness should be less than 0.1/1000, while the deviation in lateral levelness should be less than 0.05/1000. The alignment of the fan’s couplings should be carried out in accordance with the requirements specified in the accompanying technical documents and standards; at the same time, the conditions under which the fan operates under thermal load must also be taken into account, with the alignment data being adjusted accordingly. 1.3.6 Construction Procedures (1) Cylinder Furnace Construction Procedure: Cutting and assembling steel structure columns and beams, cutting reinforcement plates and furnace wall panels; rust removal and application of primer. The steel structure of the radiation chamber is prefabricated in three sections. The steel structure of the convection section is also prefabricated, along with the installation of the tube sheet frames. The furnace tubes in the radiation chamber are welded and installed. The lining of the radiation chamber is constructed. The ladder platforms in the convection section are prefabricated and installed. The lining of the convection section is installed. The convection furnace tubes are installed. The steel structure above the convection section is installed. The furnace tubes are pressure-tested. Elbow boxes and doors are installed. Inspections and acceptance are carried out. The internal components of the radiation chamber are installed. The lining of the radiation chamber is further constructed. The roof of the radiation chamber is installed. The ladder platforms in the radiation chamber are prefabricated and installed. The bottom columns of the radiation chamber are installed to ensure levelness. The ring beams of the radiation chamber are prefabricated and installed. The three sections of the steel structure for the radiation chamber are assembled, along with the installation of single columns. (2) Square Box Furnace Construction Procedure: Installation of internal components of the radiation chamber. Construction of the lining of the radiation chamber. Installation of furnace tubes in the radiation chamber. Prefabrication and installation of ladder platforms in the radiation chamber. Cutting and assembling steel structure columns and beams, cutting reinforcement plates and furnace wall panels; rust removal and application of primer. The steel structure of the radiation chamber is prefabricated in two sections and one frame. The steel structure of the convection section is prefabricated as a whole. The radiation chamber sections and frame are installed, with levelness checked. The bottom of the radiation chamber is installed (no installation at the collector pipe location). The north side furnace wall and roof of the steel structure radiation chamber are installed. The convection section is installed as a whole. The ladder platforms in the convection section are prefabricated and installed. The south side furnace wall is installed. The lining of the radiation chamber is completed. The convection furnace tubes are installed. The steel structure above the convection section is installed. The lining of the convection section is constructed. The furnace tubes are pressure-tested. Elbow boxes and doors are installed. Inspections and acceptance are carried out. (3) Prefabrication of Steel Structures: Rust removal and painting of raw materials. After the steel materials pass the inspection, rust removal and painting are carried out first. Sectional steels are cleaned using shot blasting, while steel plates are cleaned using sandblasting. The rust removal level must comply with the requirements specified in the current standard “Grade of Rust and Degree of Rust Removal on Steel Surfaces before Painting” GB8923-88. Apply two coats of rust-inhibiting primer to the steel structure. The topcoat is applied after the construction of the main body of the heating furnace is completed, and after the weld seams and damaged areas have been repainted with primer. The paint thickness should meet the design specifications. The specific anti-corrosion requirements for various components are as follows: Outer surfaces of the heating furnace body, chimney, and flue – rust removal level Sa2.5; paint to be determined. Inner surface: After derusting to grade Sa2.5, apply two coats of E06-18 zinc silicate primer, and two coats of W61-200 high-temperature resistant topcoat. For cutting, H-shaped steel is cut using a steel cutting machine, while smaller pieces of steel are cut with a toothless saw or by gas cutting. 2 Before cutting the wall panels for the furnace, arrange them properly first; it is advisable to lay the panels horizontally for the side walls, furnace bottom, and furnace top ； The boarding direction for the end walls is longitudinal, which helps to save more materials. A better method can also be chosen depending on the dimensions of the sheets upon arrival. 3 After cutting, burrs, slag, and spatter must be removed thoroughly. The ends of the parts that do not require welding should be polished smooth, and an anti-rust primer should be applied again. 4 For sheet thicknesses less than 12 mm, a sheet cutting machine is used for cutting; for thicknesses greater than 12 mm, a semi-automatic cutting machine is employed. The burrs on the edges of the cut sheets should be removed promptly. 5 Whether it is profiles or sheets, mark them promptly with lead paint after cutting, and arrange them neatly according to the specifications. 6 The allowable tolerances for gas cutting shall comply with the provisions in Table 3-2 below. Table 3-2: Allowable tolerances for various parameters (in mm): Part width and length – ±3.0; Planeness of the cut surface – 0.05t, with a maximum value of 2.0; Maximum depth of cut marks – 0.2; Maximum depth of local notches – 1.07. The allowable tolerances for mechanical shearing are shown in Table 3-3 below. Table 3-3: Allowable tolerances for various parameters (in mm): Part width and length – ±3.0; Maximum edge defects – 1.0; Perpendicularity of the ends of steel sections – 2.0; Diagonals of wall panels – 3.0. (4) The radiation chamber of the steel structure’s boxed furnace is prefabricated in two panels and one frame, as shown in the figure below: North side panel, East side panel, West side panel, Middle frame. 3 The convection chamber of the cylindrical furnace is lifted as a whole after the pipe sheets are installed in place ； The convection chamber of the box furnace is also prefabricated and lifted as a whole. 4 All assembly work for the steel structures is completed at our Liuhe prefabrication plant before being transported to the site for installation. 1.3.7 Construction technical requirements and quality standards: The construction technical requirements and quality standards for the furnace lining and furnace tubes are detailed in the construction technical measures. 1.3.8 Material acceptance: All materials such as steel sections, steel plates, steel pipes, and welding electrodes must come with quality certificates upon arrival; before fabrication and installation, it is necessary to check these certificates to determine whether they meet the relevant quality inspection standards and the specifications outlined in the drawings. 2 Visual inspection: When the surface of the steel contains defects such as rust, pitting, or scratches, the depth of these defects shall not exceed 1/2 of the negative deviation value of the steel’s thickness. The 3 bolts, as well as the welding materials and coatings (primer, topcoat, etc.) used for the steel structure, must all be accompanied by quality certification documents and must meet the requirements specified in the design documents. 4 Any modification to the design or substitution of materials must obtain written consent from the original design agency. 1.3.9 Hole Drilling and Friction Surface Machining 1 All bolt holes shall be machined mechanically; gas cutting for hole creation is strictly prohibited. 2 The surface roughness of the bolt holes should generally meet the requirements specified in the design documents. 3 Interconnected components should be drilled. After the bolt holes are drilled, the allowable deviation in the hole spacing between any two holes within the same group shall meet the requirements specified in Table 3-4 below; the allowable deviation in the hole spacing between the end holes of adjacent groups is ±1.5 mm. Table 3-4 Allowable tolerances for bolt spacing: ≤500〉500–1200〉1200–3000〉3000 (mm): ±1.5±2.0±3.0±5.0 Note: ① On the same component, the bolt holes that connect the same end plate, intermediate tube support, and elbow box form one group ； ②On the same member, when the total spacing between consecutive bolt holes is greater than 4 m, the bolt holes within every 4-m length range form one group. 1.4 Technical requirements for the prefabrication of basic components 1: Before cutting, it is necessary to check whether the specifications and material of the steel sections used meet the design requirements ； Visual inspection: The outer surface of the steel profile should not exhibit severe rust, damage, or flaking. 2 The main load-bearing beams should be made from solid pieces of material. If splicing is required, written consent from the design agency must be obtained, and the location and type of the splicing joint must be determined based on the stress conditions of the components. The locations of other beam-column splice joints should be offset by more than 300 mm from the joint area. 3 For cutting steel materials in steel structures, mechanical cutting is preferred; when the steel plates are thick, oxy-acetylene cutting can also be used. The cut pieces should have any burrs or impurities on their edges removed. 4 The splicing at the installation joints of steel columns shall be carried out in accordance with the requirements of the drawings. The flanges of H-shaped steel should be joined at a 450 angle, while the web should be joined in a direct manner. 5 Splicing of non-main girders: H-shaped steel girders should use flanges of 450, with the web connected directly. For other types of steel beam sections, a web thickness of 450 is used, while the flanges are joined directly to each other. 6 When welding steel structures, the amount of weld contraction should be taken into account, and stricter welding procedures and methods should be employed to keep welding deformation to a minimum. 7 During correction, the hot working temperature for carbon steel should not exceed 900°C; the corrected structural members must be free of cracks or excessive thickness. 8 After the aforementioned basic components are prefabricated, they are labeled. When assembling the 9 components, it is necessary to ensure that their specifications and dimensional sizes meet the requirements. The prefabrication and pre-assembly of steel frames should be carried out on a stable and level platform. When turning over and lifting the column pieces, attention should be paid to the stiffness of the components; reinforcement is generally required to prevent deformation during lifting. 1.5 Technical requirements for prefabrication of steel structures 1 Prefabrication of the frame 1) Allowable deviation in column length: ±3.0 mm 2) Allowable deviation in the straightness of columns: 20 mm 3) Allowable deviation in the straightness of the radial section cylinders is 12 mm; the allowable deviation in height is ±5.0 mm, the allowable deviation in circumference is ±15.0 mm, and the ellipticity should not exceed 10 mm. 4) The allowable deviation for the position of bolt holes on the block base plate is ±2.0 mm. 5) The allowable deviation for the height of the flow chamber frame is ±4.0 mm, while the allowable deviation for its width is ±3.0 mm. 1.6 Prefabrication of the platform ladder 6) The allowable deviation for the length of the platform can be calculated as -2 to 0 mm per 1000 mm of length; the total allowable deviation for the entire length is -10 to 0 mm ； The allowable deviation for width is ±3.0mm ； The difference between the lengths of the two diagonals should not be greater than 6.0 mm. 7) The deflection vector height on each side of the platform shall not exceed 6.0 mm when the platform length is 6 m or less ； When the platform length is greater than 6m, it should not be greater than 10.0mm. 8) The allowable deviation for the sub-length is ±5.0mm ； The allowable deviation for width is ±3.0 mm. 9) The allowable deviation of the angle between the stair tread and the side beam is ±10. 10) The vertical deflection vector height of the member shall not exceed 0.1% of its length. 11) The allowable deviation for the step spacing of the son is ±2.0 mm. 12) The spacing between the pole columns shall not exceed 1000 mm. 13) The platform grating shall be welded to the platform beam; there should be no less than 4 welds per meter in length (evenly distributed), with each weld being approximately 100 mm long. 1. Technical requirements for the installation of steel structures (1) Re-inspection of the foundation: 1) Before installing the steel structure, a thorough inspection of the foundation must be carried out. The quality of its casting, its external dimensions, the elevation of the foundation surface, as well as the relevant dimensions between the column feet, along with the spacing, verticality, exposed length, and thread length of the anchor bolts, must all comply with the specifications outlined in the design documents. 2) The basic dimensional dimensions, elevation, surface flatness, and the spacing between the longitudinal and transverse axes shall comply with the following requirements: (1) The allowable deviation for the elevation H of the foundation top surface is 0–-10.0 mm ； (2) The allowable deviation for the axis spacing between adjacent foundation rows and columns is ±3.0 mm ； (3) The allowable deviation for both the diameter of the center circle of the cylindrical furnace foundation and the spacing between adjacent foundations is ±3.0 mm ； (4) The allowable deviation for the elevation of the top surface of the foundation bolts is 0–+10.0 mm ； (5) The verticality deviation of the bolt shall not exceed 1% of the length of the bolt protruding from the foundation surface ； (6) The allowable deviation for the distance between adjacent bolts is ±2.0 mm ； (7) The allowable deviation of the bolt center from the foundation axis is ±2.0 mm ； (2) A steel shimming plate is placed between the column base plate and the foundation surface. On the upper surface of the base, pitted areas should be created within a range of 100×100 mm; the diameter of these pits must be at least 15 mm, and their depth must be at least 6 mm. Level the bottom of the shims, then place the pre-made 100×100 shims on the foundation. The shims should be secured firmly and leveled; no more than four shims per set should be used. Gently tap them with a hammer to level them so that all shims are at the same height. Before installing the frame, use a level or horizontal gauge to ensure that the upper surface of each set of shims is level. The levelness requirement between the shims of the same furnace is ≤2mm. (3) Allowable deviations in the geometric dimensions of steel structure frames after installation: 1) The allowable deviation in the elevation of the frame column foot plates is ±2.0 mm ； 2) The allowable deviation in the verticality of the frame columns shall not be greater than 15.0 mm ； 3) The horizontal deviation of the beam shall not exceed 0.1% of the beam length, and shall not be greater than 5.0 mm ； 4) The verticality deviation of the steel structure at the bottom of the furnace shall not exceed 3.0 mm, and the verticality deviation of the cylinder shall not exceed 12 mm. The radiant roof beams should be straight; the allowable deviation in beam spacing is ±3.0 mm, and the levelness deviation should not exceed 3 mm. 5) The allowable deviation for the height of the flow chamber frame is ±4.0 mm, the allowable deviation for the width is ±3.0 mm, and the verticality should not exceed 5.0 mm. The difference between the inner diagonals should not be greater than 1/1000 of the diagonal length, nor should it exceed 10 mm. 6) The height deviation of the cylinder body is ±5.0 mm; the perimeter deviation shall not exceed 18 mm, the roundness deviation shall not exceed 10 mm, and the verticality deviation shall not exceed 12 mm. (4) Installation of platform ladders 1) The allowable deviation for the platform’s elevation is ±10.0 mm. 2) The levelness of the platform beam shall not exceed 0.1% of the beam length, and shall not be greater than 20.0 nmm. 3) The verticality deviation of the platform pillars shall not exceed 0.1% of the pillar height, and shall not be greater than 15.0 nmm. 4) The allowable deviation for the height of the platform railing and the spacing between the columns is ±10.0 mm. 5) The verticality deviation of the straight ladder shall not exceed 0.1% of the ladder’s height, and shall not be greater than 15.0 mm. 6) The minimum overlap length between the steel grating and the platform beam shall be greater than 20.0 mm. (5) Installation of furnace wall panels: Due to the large area of the furnace wall panels, welding and lifting-induced deformation is likely to occur, so special attention must be paid during construction. The steel plate should be leveled before prefabrication to ensure the quality of assembly. The welding shrinkage should be taken into account when cutting steel plates. Mark the positions of the profiled steel and vertical rebar, install them, weld the profiled steel and vertical rebar together, then assemble the steel plates; first weld the fillet welds between the welded profiled steel and vertical rebar and the steel plates, and finally weld the butt welds of the steel plates. The butt welds should be welded in segments in a progressive manner to reduce welding deformation. (Generally, short welds are welded first, followed by long welds, with appropriate allowance for expansion and contraction.) The intermittent welding of steel plates and vertical reinforcement bars should be carried out by marking according to the design requirements, to ensure uniform welding lengths and intervals. The intermittent welding, just like continuous welding, must result in full weld beads with a height that meets the design specifications. 6) Installation of insulation nails and other components: 1) When marking the positions for the insulation nails, a horizontal tube should be used in the radiation chamber to establish an installation reference line for marking. 2) Before installing the insulation nails, mark the installation lines according to the diagram; the density of these marks should be increased at corners and on the roof surface. 3) The installation of the nozzles should ensure the appropriate external extension height and internal extension length. 7) Installation of furnace accessories: 1) For the inspection ports and explosion-proof doors, inspections should be carried out prior to their installation; upon arrival, these ports and doors should be free of missing parts or damage, with intact sealing gaskets. The installation location is correct and meets the design requirements. 2) Installation of burners at the furnace bottom: The installation of burners must comply with the following requirements: The installation orientation and the position of the pipe openings must be correct. The installation work should be carried out in coordination with furnace construction. First, install the special-shaped bricks, then insert the burner assembly into the pre-made holes and secure it with bolts. The expansion gap between the outer side of the burner’s special-shaped bricks and the refractory lining at the furnace bottom shall meet the design requirements. Position of the high-speed burner through the convex surface of the burner panel. The oil gun conduit is located at the center of the burner, with a deviation of no more than 3 mm; the allowable verticality error for the oil gun should be no more than 5 mm. 3) Installation of the manhole: The manhole is installed after the furnace wall panels have been installed and welded. It is necessary to ensure that it is placed in the correct position and that the welding is firm and secure. The lining of the manhole can be installed simultaneously with the construction of the furnace. 2 Welding 2.1 General Principles 1 Welding work on steel structures must be carried out by welders who hold valid certificates. 2 The welding rod should be baked according to the instructions. 3 Welding work should be carried out after the components have been aligned and their geometric dimensions have been verified to be satisfactory. Before welding, oil, rust, and other contaminants on the surface and in its surrounding area must be removed. After welding, the slag and spatter should be removed promptly. 4 When any of the following conditions exist in the welding environment, effective protective measures must be taken; otherwise, welding is prohibited. 1) When welding manually, the wind speed should be greater than 8 m/s ； 2) Relative humidity greater than 90% ； 3) Rain and snow conditions. 5 After welding is completed, for welds in ordinary carbon steel structures, visual inspection should be carried out after they have cooled to the ambient temperature. 6 The surface quality of the weld shall meet the following requirements: 1) The weld shall have a good shape. The weld surface must be free of defects such as cracks, slag inclusions, pinhole pores, and arc pits; no slag or spatter shall remain on the weld surface after cleaning ； 2) The depth of undercut on the surface shall not exceed 0.5 mm; the continuous length of undercut shall not be greater than 100 mm. The total length of undercuts on both sides of the weld shall not exceed 10% of the length of that weld. 7 The allowable deviation for the length of intermittent welds is 0 to +10 mm. 8 The dimensional dimensions of the weld shall meet the requirements of the drawings. 9 For welds for which PT inspection is required, their quality shall meet the Grade II or Grade Ш standards for ultrasonic testing as specified in the current standard \"Non-Destructive Testing of Pressure Vessels\" JB4730. 2.2 Specific welding requirements 1 Groove preparation: In all areas where grooves are required according to the drawings, they must be prepared strictly in accordance with those specifications. Samples should be made to check the groove angle; depending on the actual circumstances, either gas cutting or manual grinding with a wheel can be used. All grooves created by gas cutting must be ground before welding to remove the oxide layer formed as a result of gas cutting. 2 For the welding of steel structures, E4316 electrodes are used; the quality grades of butt welds and fillet welds shall meet the grade 2 and grade 3 requirements specified in GB50205-2001, respectively. 3 For welds with a length greater than 300 mm, especially those on furnace wall panels, a symmetric segmented progressive welding method should be employed to reduce welding deformation. When arranging the furnace wall panels, the joints of the panels should be positioned as close as possible to the flanges of I-beams or channel beams in order to reduce welding deformation. The wire energy should also be controlled and not made too high. 2.3 For the welding of furnace tubes, refer to the \"Operating Instructions for Welding Furnace Tubes.\" 2.4 Welding of wall panels: The welding sequence for wall panels is as follows – first weld the joints, then the fillet welds connecting them to the steel structure, and finally the butt welds between the panels ； Weld the outside first, then the inside ； Weld the short welds first, then the long welds. Welding requirements for wall panels: Low heat input should be used for welding wall panels, and skip welding or backstep welding should be employed to minimize welding deformation. 2.5 Transportation and lifting are carried out using 40T and 20T trucks. Lifting: The steel structural components of the radiation chamber, the furnace tubes in the radiation chamber (which are of great height), the furnace roof, the transition sections, and the steel structures for the convection area are lifted using 160T cranes as the main lifting equipment. Due to their height, the flue dampers, baffles, and compensators are lifted using 160-ton truck cranes. For the remaining lifting tasks, where the weight is less than 10 tons, 50T truck cranes are used as the main lifting equipment. The specific lifting measures and plan are detailed in the «Large-Scale Lifting Plan». 2.6 Product Protection Measures 2.6.1 Before installing the steel structure frame, a professional lifting engineer must, based on the actual conditions on site, calculate and select appropriate lifting points and methods to carry out the lifting process, in order to prevent twisting or deformation during lifting. Once the beams and columns have been aligned properly, they should be welded in place immediately. Throughout the entire installation process, professional surveyors must monitor the work. 2.6.2 Steel structures should not have components such as temporary supports welded to them. Temporary components and supports that need to be welded due to construction requirements should be removed immediately after construction, the weld spurs should be removed, and the base material must not be damaged. 3.7.3 After removing the scaffolding used in steel structure construction, the wire ends must be cleaned thoroughly. 3.7.4 After the labor protection components for ladder platforms are prefabricated, they should be painted promptly to prevent corrosion; meanwhile, measures must be taken to avoid damage due to compression during handling and transportation. The installed platform railings must not be used to lift heavy objects or to serve as a construction platform. Once the ladder platforms have been constructed, they must not be cut or removed arbitrarily. If removal is indeed necessary for construction purposes, safety precautions must be put in place, and the platforms should be restored to their original state as soon as possible after construction is completed. After the construction of the ladder platform is completed, the weld beads should be polished smooth using a grinder before applying paint. 3.7.5 When removing the scaffolding used for the lining, it must be transferred manually to carry the scaffolding rods and stepping boards out of the furnace; it is strictly prohibited to damage the lining. 3 Construction Technology Management 3.1 Preliminary Technical Preparation 3.1.1 Technical Briefing The technical quality department shall organize a technical briefing for this plan; construction is not permitted without such a briefing. The responsible engineer shall provide instructions to the construction workers, quality inspectors, and team leaders, and records thereof shall be kept. 5.1.2 The construction team adheres to the principle of “five no’s for construction”: no construction shall take place if the drawings are unclear or the tasks are not defined. 2 Work will not proceed if the instructions are unclear or the standards are not defined. 3 Work will not proceed if the materials lack a certificate of conformity or are substandard. 4 Construction will not proceed if the testing equipment and instruments are substandard or not in good condition. 5 Construction will not proceed without qualified safety technical briefing measures. 3.2 Technical management during construction 3.2.1 Coordination with on-site construction management 1 Construction workers shall guide teams and workers in carrying out construction in accordance with the approved construction technical plans; no modifications to the construction methods shall be made without approval. 2 Inspection and management of the certificates of conformity and warranty documents for engineering materials, accessories, and equipment. 1) Certificates of conformity and warranty documents must be reviewed before the use of materials, components, and equipment; copies from the supply department must be obtained, and they can only be used after approval ； 2) The construction worker shall promptly review the items listed in the certificate of conformity and warranty letter; if any discrepancies or requirements are found, appropriate actions shall be taken immediately, and the situation shall be reported to the technical supervisor ； 3) Materials, components, and equipment without certificates of conformity and warranty documents shall not be used in construction projects. 4) The furnace lining materials must be accompanied, at the time of delivery, by a quality inspection report and certificate of conformity issued by the manufacturer’s quality control department for batch testing, as well as a copy of a comprehensive inspection report issued by a technical supervision agency at or above the provincial level. 3 During the construction process, it is necessary to properly carry out handover of work stages and inspection of concealed works. Procedure handover must be carried out between different processes. There must be a procedure to be confirmed by the general contractor; concealment can only take place after it has been verified by the general contractor’s on-site engineer. 4 Construction shall be carried out in accordance with the construction specifications, record forms, and drawing documents specified by the general contractor, with proper records to be kept. If the general contractor does not have any specific requirements regarding the record forms, then the SH3503 standards of Sinopec Group Company and the specific requirements of the construction specifications shall be followed. 5. Work closely with the general contractor to promptly address and resolve technical issues that arise during construction, ensuring the smooth progress of the project. 3.2.2 Construction record management 1 Self-inspection records are important original documents that serve as the basis for task handover and quality inspection; the work teams must keep proper records, while the construction supervisors should conduct timely inspections and provide oversight. 2 The construction self-inspection records must be clearly explained to the workers during the technical briefing, and record forms should be provided; the technical department should conduct regular inspections and correct any issues found promptly. 3 The construction workers shall carefully maintain the construction records required by the handover and acceptance procedures, ensuring that they are accurate, reliable, complete, and thorough. The construction records, as well as the evaluations of the quality of individual project components, should be kept in sync with the project progress, and approvals from quality inspectors, the project owner, the general contractor, and other relevant parties should be obtained in a timely manner. 4. In accordance with the requirements for archiving technical documents, the construction worker enters the records into the computer daily to enable computer-based management. 3.3 Project Completion Management 3.3.1 Three Inspections and Four Determinations During the final stage of project construction, the chief engineer organizes technical and quality personnel to participate in the three inspections and four determinations carried out by the owner and the general contractor (Three Inspections: checking for design omissions, identifying potential quality issues in construction, and examining unfinished work) ； Four fixations: For the issues identified during the inspection, assign tasks, designate personnel, determine measures, and set deadlines for rectification; create a plan to address these issues and keep records of it. 3.3.2 Cancellation of unfinished projects: For the projects identified as part of the “three inspections and four determinations” process, the chief engineer should take the lead, in collaboration with departments such as technology, production, and quality, to cancel each project one by one according to the plan outlined for such cancellations. Strengthen the inspection of the completion status of projects subject to cancellation, and reschedule work on those that do not meet quality standards without exception. 3.4 Management of handover documents The main contents of handover documents include various inspection and test records during the construction process, as well as as-built drawings. 4.4.1 Comply with the requirements for technical documents to be delivered as specified in the contract; unless the general contractor has special requirements, the requirements outlined in the \"Regulations on Technical Documents for Completion of Petrochemical Engineering Projects\" (SH3503-2001) shall apply. 4.4.2 As-built drawings: Consist of the construction drawings that have been revised and stamped with the as-built seal, along with design modification notices, project correspondence documents, and material substitution forms. 4 Quality Assurance and Measures for Creating High-Quality Projects 4.1 Quality Management Objectives 4.1.1 100% qualification rate for individual projects 4.1.2 Excellent rate for individual projects of over 95% ； 4.1.3 The first-pass welding success rate is over 95% ； 4.1.4 The pass rate for project measurement points shall be over 90% ； 4.2 Quality control during the construction process 4.2.1 Quality control of construction preparation 1 Before starting construction, it is necessary to adhere to the \"four principles\": adhering to the review of drawings, adhering to the preparation of construction technical documents, adhering to the explanation of construction plans and measures, and adhering to technical training. 2 Prepare a construction plan, which shall be implemented after approval by the owner. 3 Personnel in special types of jobs must work with valid certificates. 4 For welding at critical locations, the welders involved must take an exam before starting work; only after passing the exam and obtaining approval from the owner may they proceed with the welding. 4.2.2 Quality control during the construction process. 1 During construction, it is essential to control the “five key aspects”: the construction procedure, operating procedures, inspection of raw materials, acceptance of concealed works, and handover between different construction stages. 2 Control of the working environment: The environmental temperature, humidity, wind speed, etc., in the welding area must meet the requirements for welding. 3 Control of Quality Control Points: Before construction, a list of quality control points for the project should be prepared. Sequence Number | Quality Control Point | Content | Grade | Quality Record Form
1 | Inspection and verification of base layer rust removal | AJ115 | | |
2 | Inspection of the number of coats and thickness of the anti-corrosion base layer, intermediate layer, and top layer | B | J117 | |
3 | Inspection of the axis, elevation, and verticality of the steel structure | B* | J211 | |
4 | Assessment of welders | B* | J116 | | Welding procedure qualification report | 6 | Review of X-ray films | B* | J123 |
7 | Hydrostatic testing of the furnace tube system | AJ317 | | |
8 | Inspection of the installation of spring supports and hangers for the radiant tubes, as well as the position of the guide tubes | AJ318, J321 | | |
9 | Verification of conditions prior to furnace construction | AJ128 | | |
10 | Inspection of the refractory concrete inside flues and chimneys | BJ115, J320 | | |
11 | Inspection of the refractory lining | BJ115, J320 | | |
12 | Inspection to ensure that the furnace roof and walls are waterproof | BJ320, J321 | | |
13 | Verification of conditions prior to sealing the furnace | AJ128 | | |

4.3 Labeling: To ensure accurate identification of raw materials, finished products, semi-finished products, and their status during the construction process, to facilitate random inspections by representatives of the general contractor and the supervisory party, to support the smooth conduct of various management tasks within the project team, and to meet requirements related to traceability, it is necessary to strengthen the labeling management of raw materials, finished products, and semi-finished products. Labels should be attached and hung by quality inspectors, who must keep records of these labels so that they can be replaced if necessary. Construction teams should promptly check for any labels that have come loose during transportation or installation, and inform the quality inspectors so that the labels can be replaced. The specifications for adhesive labels are 90×56 mm, with a 3 mm border around all edges ； The specifications for the metal nameplate are 180×111 mm. The content to be filled in on the adhesive labels is as follows: In the “Inspector” field, the quality inspector appends their identification stamp; the inspection results for each processing step are marked with a “Qualified” stamp by the quality inspector ； The person in charge of the construction process signs in the “Responsible Person” column. The label format is shown in Table 5-1 below: See Table 5-1 on the following page. Name of the steel frame installation marking device, Number, Person in charge of assembly, Person in charge of welding, Person in charge of installation, Inspector, Date